SAN FRANCISCO (Reuters) - Aiming to shore up support among his Republican base, a politically weakened Gov. Arnold Schwarzenegger seems almost certain to veto a bill that would allow gay marriage in California, political analysts said on Wednesday.

The bill, passed late on Tuesday in California's Democrat-led Assembly, marked the first time a state legislature in the United States has endorsed gay marriage. The state Senate backed the bill last week.

A spokeswoman for Schwarzenegger said the governor supports Proposition 22, a voter-approved measure defining marriage as between a man and woman. He also believes the courts are the "correct venue" for deciding on the state's ban on same-sex marriages, she said.

Gay marriage is under review in California courts following San Francisco Mayor Gavin Newsom's decision in 2004 to issue marriage licenses to same-sex couples -- a move that set off a national debate.

California's Supreme Court has invalidated the San Francisco licenses, but left the wider issue of whether the ban on gay marriage is constitutional to lower courts.

Democrats admit the gay marriage bill is largely a symbolic gesture and they do not expect Schwarzenegger to back it.

"It certainly seems like he wants the courts to make the decision for him, but we truly feel like we did the right thing," said Richard Stapler, an aide to Assembly Speaker Fabian Nunez.

Republican media consultant Wayne Johnson said it was inconceivable Schwarzenegger would sign the bill because his approval ratings have slumped, leaving him with only Republican support. "The people who are his strongest supporters are among the least likely to support this bill," said Johnson.

Schwarzenegger has struggled with sinking poll numbers and faces an uphill struggle to convince voters to back ballot measures in a special November election he called.

A Field Poll released on Wednesday found 56 percent of California voters are not inclined to support Schwarzenegger if he seeks re-election.

But voters hold the state legislature in even lower regard so Schwarzenegger would be able to veto the gay marriage bill claiming it as a defense of existing state law.

"He can wrap himself in the rule of law and say, 'The people have spoken,"' said Tony Quinn, co-editor of the California Target Book, which tracks state political races. "This is probably one issue in which Schwarzenegger is probably a winner at a time when he has very few issues going his way."

The gay marriage bill would have a better chance of surviving if Schwarzenegger was not on the defensive before the November election, said Allan Hoffenblum.

"There's no intolerance here but he's aware that ... there is still not a political consensus on the issue" of gay marriage, said Hoffenblum, who noted that Schwarzenegger has supported expanded rights for gay couples registered as domestic partners.

Gay rights advocates celebrated as the California Legislature became the nation's first lawmaking body to allow same-sex marriages, but acknowledged Wednesday that it would be months or years more before the champagne flows at weddings.

Besides the immediate hurdle of clearing Gov. Arnold Schwarzenegger's desk, the bill that passed the Assembly by the minimum number of votes late Tuesday also faces a pair of legal and political challenges that could ultimately untie the knot.

The Republican governor, a moderate on social issues, has repeatedly said that while he has no problem with gays winning the right to wed, he thinks the hot-button issue should be decided in the courts or at the ballot box. But he has not yet pledged to veto the bill after Democrats forced him to take a stand.

Schwarzenegger refused to comment on the gay marriage legislation when he spoke to the media at a Salvation Army warehouse Wednesday, saying he wanted to keep the focus on relief efforts for victims of Hurricane Katrina. He has until Oct. 9 to sign, veto or let the bill take effect.

GOP strategist Kevin Spillane said Wednesday that gay marriage supporters should not take the governor's silence as a sign of hope.

"The strongest supporters of Arnold Schwarzenegger right now are Republican voters, and they are strongly opposed to gay marriage," Spillane said. "If the governor were to sign the legislation, the support would collapse among his base. It would negatively affect turnout for the special election, as well as badly damage his expected re-election campaign."

In the unlikely event the governor signs it into law, the legislation still would face an immediate legal challenge from conservative groups who claim the Legislature's action violated an initiative California voters approved five years ago. Proposition 22 stated that "only marriage between a man and a woman is valid or recognized in California."

Under California law, voter-passed initiatives only can be repealed through another initiative. Since then, opponents and supporters of gay marriage have argued over whether Proposition 22 applied to marriages performed in the state or were crafted simply to prevent California from sanctioning same-sex marriages performed elsewhere.

To get around that question, Assemblyman Mark Leno, the main author of AB849, included a provision stating it legalizes only in-state same-sex marriages. Gays and lesbians who married in Massachusetts, for instance, the only U.S. state that now allows gay marriage, still could not have their unions recognized if they moved to California.

But Jordan Lorence, senior counsel with the Christian legal group Alliance Defense Fund, said it was far-fetched to assume that Proposition 22's sponsors intended such a narrow meaning. He said the Legislature acted outside its authority.

Although Proposition 22 passed in March 2000, no court so far has been asked to decipher its scope. The Alliance Defense Fund immediately would seek a court ruling on which interpretation is correct if Schwarzenegger supports the bill, Lorence said.

"The lawmakers who voted for AB849 could not get up and say we believe Proposition 22 is unconstitutional and we think the people are a bunch of ignorant bigots so we are going to do the right thing," Lorence said. "The only way they can superficially justify what they did is to make a very technical and legalistic argument that Proposition 22 is limited to certain things."

Meanwhile, a state appellate court is considering appeals of a lower court ruling earlier this year that overturned Proposition 22 and a 1978 law that first formally defined marriage as a union between a man and a woman. If the appellate court and eventually the California Supreme Court agree that gay marriage bans are unconstitutional, it would clear the way for the nation's most populous state to follow Massachusetts.

"That's why we have a Constitution, to make sure nobody's fundamental rights are trampled because of the latest public opinion poll," said Kevin Cathcart, executive director of Lambda Legal, a gay rights legal group. "Whether or not Gov. Schwarzenegger fulfills his promise to be a governor for all the people of California by signing this bill, we will continue to work within the judicial system until same-sex couples in California have full equality."

Even a definitive opinion from the state's highest court, however, may not end the debate. Opponents of same-sex marriage are working to qualify initiatives for the 2006 ballot that would amend the state Constitution to ban gay marriages and strip same-sex couples of domestic partner rights — putting the matter out of reach of both the courts and the Legislature.

Lorence predicted that whatever ball lands next — Schwarzenegger's signature, a court ruling upholding the gay marriage bill or a Supreme Court ruling that finds the state's marriage laws are constitutional — it would spur voters to express their dissatisfaction by passing the proposed amendments.

"The bottom line you could draw today is that what the Legislature did is not the final word on this," he said. "There is a lot more that is going to go on before this is done. The celebrations have started too early."
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